SNR S2940-8G-v2, Configuration Manual

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SNR S2940-8G-v2 Switch Configuration Guide
IPv4 Multicast Protocol
2. Destination Control
We want to limit users with address in 10.0.0.0/8 network segment from entering the group of
238.0.0.0/8, so we can make the following configuration:
Firstly enable IGMP snooping in the VLAN it is located (Here it is assumed to be in VLAN2)
Switch(config)#ip igmp snooping
Switch(config)#ip igmp snooping vlan 2
After that, configure relative destination control access-list, and configure specified IP address
to use that access-list.
Switch(config)#access-list 6000 deny ip any 238.0.0.0 0.255.255.255
Switch(config)#access-list 6000 permit ip any any
Switch(config)#multicast destination-control
Switch(config)#ip multicast destination-control 10.0.0.0/8 access-group 6000
In this way, users of this network segment can only join groups other than 238.0.0.0/8.
3. Multicast strategy
Server 210.1.1.1 is distributing important multicast data on group 239.1.2.3, we can configure
on its join-in switch as follows:
Switch(config)#ip multicast policy 210.1.1.1/32 239.1.2.3/32 cos 4
In this way, the multicast stream will have a priority of value 4 (Usually this is pretty higher, the
higher possible one is protocol data; if higher priority is set, when there is too many multicast data,
it might cause abnormal behavior of the switch protocol) when it gets to other switches through
this switch.
40.2.4 DCSCM Troubleshooting
The effect of DCSCM module itself is similar to ACL, and the problems occurred are usually re-
lated to improper configuration. Please read the descriptions above carefully. If you still can not
determine the cause of the problem, please send your configurations and the effects you expect
to the after-sale service staff of our company.
40.3 IGMP Snooping
40.3.1 Introduction to IGMP Snooping
IGMP (Internet Group Management Protocol) is a protocol used in IP multicast. IGMP is used
by multicast enabled network device (such as a router) for host membership query, and by hosts
that are joining a multicast group to inform the router to accept packets of a certain multicast
address. All those operations are done through IGMP message exchange. The router will use
a multicast address (224.0.0.1) that can address to all hosts to send an IGMP host membership
query message. If a host wants to join a multicast group, it will reply to the multicast address of
that a multicast group with an IGMP host membership reports a message.
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